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    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Développement de matériaux mécanofluorochromes à base de polydiacétylènes comme capteurs de force ultrasensibles

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    In the context of mechanical force sensing, the development of fluorescent ultrasensitive probes is an intriguing perspective for various fields of application, like mechano-biology and mechanical engineering. In this regard, mechanofluorochromic materials that change their fluorescence properties when subjected to external mechanical stimulation may be a valid option for the design of such sensors. We present here the study of four novel mechano-responsive luminescent polydiacetylene derivatives. The systems were accurately designed to evaluate how structural changes influence their polymerization dynamics, morphology, photophysical properties and fluorescence response upon mechanical stress application. The study is carried out at the macro and nanoscale, where an atomic force microscope coupled to a fluorescence microscope were used to apply forces in the nN range and evaluate the fluorescence activation. Original tetrazine-substituted diacetylenes in the form of thin films and single crystals are confirmed to be good candidates to optically respond to forces down to the nN scale.Dans le cadre de la détection de forces mécaniques, le développement de sondes fluorescentes ultra-sensibles représente une perspective intéressante dans des domaines variés, de la mécano-biologie à la mécanique des structures. Dans ce contexte, les matériaux mécanofluorochromes capables de changer leurs propriétés de fluorescence sous contraintes mécaniques pourraient se révéler de bons candidats pour la conception de telles sondes. Nous présentons dans ces travaux l’étude de quatre dérivés inédits de matériaux fluorescents sensibles aux forces à base de polydiacetylènes. Les quatre systèmes ont été conçus spécifiquement pour évaluer l’influence de certains changements structuraux sur leurs dynamique de polymérisation, morphologie, propriétés photophysiques et leur réponse fluorescente aux sous stimulation mécanique. L’étude a été menée à la macro échelle aussi bien qu'à la nano échelle, à l'aide d'un microscope à force atomique couplé à un microscope de fluorescence pour à la fois appliquer des forces à l’échelle du nN et pour évaluer l'activation de fluorescence correspondante. Les nouveaux polydiacétylènes substitués par le fluorophore tétrazine se sont montrés de bons candidats pour répondre optiquement de façon définie aux forces jusqu'à l’échelle du nN

    Développement de matériaux mécanofluorochromes à base de polydiacétylènes comme capteurs de force ultrasensibles

    No full text
    In the context of mechanical force sensing, the development of fluorescent ultrasensitive probes is an intriguing perspective for various fields of application, like mechano-biology and mechanical engineering. In this regard, mechanofluorochromic materials that change their fluorescence properties when subjected to external mechanical stimulation may be a valid option for the design of such sensors. We present here the study of four novel mechano-responsive luminescent polydiacetylene derivatives. The systems were accurately designed to evaluate how structural changes influence their polymerization dynamics, morphology, photophysical properties and fluorescence response upon mechanical stress application. The study is carried out at the macro and nanoscale, where an atomic force microscope coupled to a fluorescence microscope were used to apply forces in the nN range and evaluate the fluorescence activation. Original tetrazine-substituted diacetylenes in the form of thin films and single crystals are confirmed to be good candidates to optically respond to forces down to the nN scale.Dans le cadre de la détection de forces mécaniques, le développement de sondes fluorescentes ultra-sensibles représente une perspective intéressante dans des domaines variés, de la mécano-biologie à la mécanique des structures. Dans ce contexte, les matériaux mécanofluorochromes capables de changer leurs propriétés de fluorescence sous contraintes mécaniques pourraient se révéler de bons candidats pour la conception de telles sondes. Nous présentons dans ces travaux l’étude de quatre dérivés inédits de matériaux fluorescents sensibles aux forces à base de polydiacetylènes. Les quatre systèmes ont été conçus spécifiquement pour évaluer l’influence de certains changements structuraux sur leurs dynamique de polymérisation, morphologie, propriétés photophysiques et leur réponse fluorescente aux sous stimulation mécanique. L’étude a été menée à la macro échelle aussi bien qu'à la nano échelle, à l'aide d'un microscope à force atomique couplé à un microscope de fluorescence pour à la fois appliquer des forces à l’échelle du nN et pour évaluer l'activation de fluorescence correspondante. Les nouveaux polydiacétylènes substitués par le fluorophore tétrazine se sont montrés de bons candidats pour répondre optiquement de façon définie aux forces jusqu'à l’échelle du nN

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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